at 16Mhz this loop should be repeated quite easily more than 20'000 times per second.(assuming hereby that 16Mhz = 16'000'000 operations per second => the loop would need 800 operations to run, which I doubt for the simple one-line command).=> It seems to me that the Arduino would at 9600 bps baud rate would fail here?

is this right?

a) What happens then. does it crash and "reboot" ?b) Does it depleat the ram?c) does it simple discard excess data? (if so which data is discarded, the earlier or the later one?)

thank you for your insights!

BTW:this is not very much relevant to my question. But maybe it has a slight impact so I want to mentionthat I use Linux and /dev/ttyACM0 to communicate via the command line.so the data arriving would arrive there.=> also, I just want to mention that I do not use the IDE (because I dislike the Java-shit "security risk"... so I code using makefiles and communication to the Arduino is done via /dev/ACM0)

at 16Mhz this loop should be repeated quite easily more than 20'000 times per second.

Up until the point that the output serial buffer is filled, yes, then you will slow to a roughly 960Hz loop rate.

Edit: Sorry - hit "post" too soon. The input and output buffers are both 64 bytes.Once the output buffer is full, your loop would slow to the line rate; as one character is transmitted, another is accepted into the output buffer, so your loop blocks.

"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.Do not send technical questions via personal messaging - they will be ignored.

I confess that I was rather surprised by that outcome. It makes sense, but I must say beforehand I was inclined to believe that the result would rather be a crash when the buffer is depleated.

That is... when using the Arduino IDE and its tools it can be that the PC-side (of the serial connection) really receives the data. But I am not sure ...

(NEW doubt)?? what if there is a blockage there? Is is independent of the "receiving-PC side" (no matter linux/windows etc) that the data is moved of? Or can the receiver cause a blockage (no matter the baud rate).

my new doubt is founded in the experience/test that if I have arduino do something like

It may be counter intuitive, but it is one of the things that makes the Arduino' bootloader so easy to use.

Yes, that may be As long as it is documented, there is no harm / confusion caused.....I must have missed it that in the Reference that talks about the Serial Connection the fact "reboot at each connection" is mentioned...